js深度優先和廣度優先遍歷語法樹

在遍歷html語法樹中用到了深度優先遍歷和廣度優先遍歷，就自己用js實現了下

//treeSearch.js
//廣度遍歷html節點
function breadthSearch(item, childProp='children'){
    const nodeList=[item]
    let index=0;
    while (index<nodeList.length){
        const node=nodeList[index++];
        if(node[childProp]){
            for(let k in node[childProp]){
                nodeList.push(node[childProp][k]);
            }
        }
    }
    return nodeList;
}
//深度遍歷html節點
function depthSearch(node,childProp='children'){
    const nodeList=[]
    const depthEach=function(item){
        nodeList.push(item);
        if(item[childProp]){
            for(let k in item[childProp]){
                depthEach(item[childProp][k]);
            }
        }
    }
    depthEach(node);
    return nodeList;
}
//廣度遍歷
function breadthEach(node,filter) {
    const nodeList=[]
    const itemList=[node]
    let index=0;
    while (index<itemList.length){
        const item=itemList[index++];
        if(filter(item)){
            nodeList.push(item);
        }
        for(let k in item){
            if(item[k]&&typeof item[k]==='object'){
                itemList.push(item[k])
            }
        }
    }
    return nodeList;
}
//深度遍歷
function depthEach(node,filter){
    const nodeList=[]
    const depthEach=function(item){
        if(filter(item)){
            nodeList.push(item);
        }
        for(let k in item){
            if(item[k]&&typeof item[k]==='object'){
                depthEach(item[k]);
            }
        }
    }
    depthEach(node);
    return nodeList;
}
module.exports={
    breadthSearch,depthSearch,breadthEach,depthEach
}

　　

測試

const fs=require('fs')
const {depthEach}=require('./utils/treeSearch')
const code=fs.readFileSync('./test.js').toString()
const ast=require("babylon").parse(code, {
    // parse in strict mode and allow module declarations
    sourceType: "module",

    plugins: [
        // enable jsx and flow syntax
        "jsx",
        "flow"
    ]
});
const arr=depthEach(ast,function (node) {
    return node.type==='VariableDeclaration'
})
console.log(arr.length)